Improvement



" FICE.

JOHN W. C. MGCURDY, OF ATWOOD, PENNSYLVANIA.

IMPROVEMENT IN CUTTER-HEADS.

Specification forming part of Letters Patent No. l93,6ii, dated July 3l, 1877; application filed June 26, 1877.

To all whom it may concern Be it known that I, JOHN W. G. MOGURDY, of Atwood, in the county of Armstrong and State of Pennsylvania, have invented certain new and useful Improvements in Gutter-Heads, of which the following is a specification Figure l is a plan view of' the groover. Fig. 2 is a plan view of the tonguer; Figs. 3 and 4, respectively, side elevations of the groover and tonguer; Fig. 5, detail, showing, in section, the groove and tongue as made in boards and adapted to form a joint.

The design of the present invention is to produce a set or pair ot' combined bits, one of which shall be adapted to cut an acuteangled groove in the edge of a board or plank, and the other a tongue ofcorresponding shape in the opposite edge; and to this end the 'said invention consists more particularly in the novel shape and construction of each set or pairs of bits, and in their peculiar adaptation and arrangement in their respective cutter heads, all as will now be vmore in detail set out and explained.

In the accompanying drawings, A and A' denote, respectively, the cutterhead for the groover and tonguer, as I denominate the head that carries the one or the other set or pairs of bits. These heads are each adapted in the usual manner upon shafts and held in place by nut a. To and upon the cutter-head A are secured in any usual or ordinary way the bits B, two of these, b, so arranged as to be on opposite sides the one from the other, are bent upward near the end so as to forni an acute angle at this point, and on one side of said bent-up portion is a cutting-edge. Alternately with these, and likewise opposite each other, are arranged the bits b', their ends turned down parallel to Jthe sides of the' cutter-head, the point of' bending being not so far away from said head as in the case ot' the bits b. Each of said bits b has, also, a cutting-edge on one side of said bent portion. All of the said cutting-edges on the bits b and b' are arranged so as to come on the same side.

On the tonguer A the bits b" and b are adapted in very similar manner to that just now explained, and in construction and arrangement diti'er from the bits b b chieliy in that the upward-bent bits b have an obtuse angle relative to the head, and are the closer of the set to the head, while the downwardlybent and parallel ones b extend out the farthest; also, the cutting-edges are made on the faces reverse to those on the groover.

lt will be thus perceived that the bits on the groover are generally made and arranged about the reverse of those on the tonguer.

ln usual adaptation the tonguer operates on a movable head, while the groover is made to work in one position 5 but the reverse of this can be used, it' desired. The bits can be kept in order very easily. It is intended that the outer side or face of each bit shall be somewhat curved. This shape or conliguration will assist materially in sharpening them, and there is no need ot' dressing on the outside; nor will it be necessary to use a lile in dressing the bits, for they can be sharpened or dressed upon any of the common grindstones used for this purpose without the least difiiculty.

rIhe joint shown in Fig. 5 has peculiar value, in that it can be easily made, the tongue and groove being readily adapted, and it is very durable because it cannot be broken till the boards are well-nigh worn out.

Having thus described my invention, I claim as new and desire to secure by Letters Patent- 1. The cutter-head A, having bits B, b, and b', combined therewith in the manner and for the purposes substantially as set forth.

2. The cutter-head A', having bits B', b, and b", combined therewith, substantially in the manner and for the purposes set forth.

In testimony that I claim the foregoing as my own, I do affix hereto my signature in presence of two witnesses.

JOHN WM. C. MCGURDY. 

